Nextleaks on twitter had twitted this some days ago,
Lumia 1820 = 1030: 5.2'' QHD /QSD805/3GB RAM/3400mAh/Lytrocamera and Visio pureview cam
now, i dont know how true this leaker is, but Lytro Style camera is in the works from Nokia from some previous leaks,
also, read that " The Qualcomm Snapdragon 805 allows phones to offer two-camera systems like the Duo Camera on the HTC One (M8). According to the chipmaker's senior director for cameras and imaging, Tim Yates, Qualcomm plans on developing a reference design that supports both stereo and depth cameras, so that phone manufacturers won't have to do it themselves from scratch."
So this twit mite be true coming from NextLeaks. Not sure though.
Also, the samsung zoom k coming, HTC M8, and iPhone getting a Nokian to work on their cams, i see 1030 happening this year, but it would take time.
Also Nokia are known to bring something new to their camera offering so they mite be working on it.
Also, Apple signing a Nokian to work on their camera's, i dont know how it would affect MS / Nokia?
Its not a single guy who builds a camera or the phone, its the team , the company who works together in making it possible, many different factors are involved.